Fuel injector pump



Nov. 30, 1937. J. w. BERHMAN ET AL 2,100,318

FUEL INJECTOR PUMP Filed Oct. 31, 1955 5 Sheets-Sheet 1 INVENTORS' \./0///\/ W. BEEl/Mfl/V PAH MON L 805/04 /0 W AQ /L ATTORNEYS Nov. 30, 1937. J. w. BERHMAN El AL FUEL INJECTOR PUMP Filed Oct. 31, 1935 3 Sheets-Sheet 2 Mm m WNW/Wm mg m 6 o 0 W 3 n O Nov. 30, 1937. J. w. BERHMAN ET AL 2,100,318

FUEL INJECTOR PUMP Filed Oct. 31, 1935 s Sheets-Sheet 5 INVENTORS JOHN VV BEBfi/MIQA e4 YMO/V A. BOG/01. /0

BY ma ATTORNEYS Patented Nov. 30, 1937 UNITED STATES PATENT. OFFICE FUEL INJECTOR PUMP Application October 31, 1935, Serial No. 47,534

'1 Claims.

Our invention relates to improvements in pumps.

One of the objects of our invention is to provide an improved construction for a pump of 5 the type more particularly adapted for fuel injectionin Diesel engines,-and which has advantages over the various constructions proposed heretofore in the way of eificiency and reliability of operation at relatively high speeds of operation and conditions of relatively high output pressures. f

Another object of our invention resides in the I provision of an improved construction for a pump of the character referred to which is relatively simple as compared with the various constructions proposed heretofore.

Other objects and advantages will hereinafter appear.

For the purpose of illustrating our invention, an embodiment thereof is shown in the drawings, in which Figure 1 is a longitudinal sectional view of a pump constructed and operating in accordance with our invention; I

Figs. 2 and 3 are sectional views taken on the lines 22 and 3-3, respectively, in Fig.1;

Fig. 4 is a sectional view similar to Fig. 2, showing a modification;

Fig. 5 is a plan view of Fig. 1, part of the pump casing being broken away to show the interior; 1

- Fig. 6 is an elevational view looking toward 1 theleft in Fig. 5;

Figs; '7 and 9 are sectional views similar to Fig.

2, showing modifications;

Fig. 8 is a view partly in section, the section being taken on the line 88 in Fig. '7;

Fig. 10 is a perspective view of the assembly of the pumping parts in Fig. 1;

Figs. 11 and 12 are detail perspective views of two of the parts in the assembly shown in Fig. 10;

Fig. 13 is a simplified, fragmentary view, show-- ing a modification; and

Fig. 14 is a fragmentary view taken from Fig. 9, showing a modification.

With reference to Fig- 1,.our' improved pump comprises a casing l provided with an annular pump or pressure chamber 12 concentric about its longitudinal axis. The pumping action is effected by complementary pumping parts l4 and i6, each being in the form of a segment of a 56 her for rocking movement about thelongitudinai axis of the pump casing relatively with respect to the part it which is fixed against movement in the casing. The pumping part or member I6 is integral with a hollow head 20 on the end of a driving shaft 22 which extends outwardly and beyond the pump casing through a cover plate 24 and a nut 26 screwed thereon to hold packing 28 in place about the shaft.

For the purpose of imparting'rocking movement to the shaft 22 and the pumping part IS, a rotating cam 30 is caused to engage a roller 32 on the end of an arm 34 fixed on the shaft. The cam 30 causes rocking movement of the pumping part IS in a clockwise direction, as viewed in Fig. 2, from the position shown through anangle slightly less than the angle .2, so that the face 36 of the part 16 is then close to but does not engage the adjacent face 38 'of the part ll. During this stroke of the part I8, 011 or other liquid previously admitted into the pump chamber between the adjacent faces 36 and 38 is forced therefrom and expelled from the pump casing by the way of an outlet passage l0 and a check valve 12 of conventional design. As the high part of the cam leaves the roller 22 at the end of the pumping stroke, the shaft 32 is allowed to rotate back under the action of a coil spring 44 having one end fixed to the packing nut 26 and its other end engaged with the arm 34. The cam surface is such that the part I8 is allowed to rotate back until it engages lightly with the abutment II, or such that at the end ofthe return stroke the part 16 falls slightly short of the part I4. As shown in Fig. 6, the ar rangement is such that the direction of force on .the nut 26, due to the tension in the spring N, is the same as thedirectionpf rotation of the nut to tighten it with respect to the cover plate 24. A compression spring 5 may be used in lieu of the coil spring 44, as shown in Fig. 13.

The coverplate 24 is secured to the pump casing by screws 46 which may be locked against loosening by a wire 48 extended and tightened about the screw heads as shown in Figs. 5 and .6. For the purpose of controlling the volume of 'oil or liquid expelled through the valve l2 for each stroke of the pumping part 16, a valve element 50 is provided, this being disposed within the.

pumping parts or members It and I6 and having '50 a sliding fit with respect thereto. The element. 50 is rotated about the longitudinal axis of the. pump casing by a control shaft 52 with which it is integral and which extends outwardly beyond the casing through a packing nut 54 screwed on 55 the outer end of a nipple 56 having a press fit in the pump casing and with which the part or abutment I4 is integral. Leakage between the shaft 52 and nipple 56 is prevented by packing 58 held in place by the nut 54. The control shaft 52 is rotated by an' arm 68 fixed to the outer end thereof. I

The oil or liquid to be pumped is admitted into the pump chamber by way of an inlet connection 62, an annular groove 64 in the pump casing, a passage 66 and a communicating annular groove 68 in the nipple 56, and passages 18 and I2 in the control shaft 52. The valve element 58 is drilled to provide passages I4 through which the oil or liquid passes from the passage 12 into the pumping chamber I2, or in the opposite direction from the pump chamber back into the passage I2.

The control or apportionment of the volume of oil pumped through the check valve 42 for each stroke of the rocking part I6 is obtained by rotation of the control shaft 52 to position the passages 14 with respect to the face 86 when the pumping part I6 is in the position shown in Fig. 2 and about to begin the pumping stroke. With the parts in their respective positions, the control element 58 being in the full-throttle position, as shown in Fig. 2, the passages M are closed shortly after the pumping part I6 starts the pumping stroke, so that practically all of the 011 between the adjacent faces 86 and 38 will be pumped out (through the valve 42. However, if

.the control element 58 is rotated in a clockwise direction to place the passage 14 in any desired intermediate position, the oil, during the corresponding initial part of the operating stroke will be pumped back through the passages 14 into .the intake passage and'until the part I6 reaches the position where it closes the passages 14, after which the oil remaining between the adjacent faces 36 and 38 will be forced out through the valve 42.

From the foregoing it will be seen that the apportionment of the oil or liquid pumped during each pumping stroke of the part I6 is possible by simply adjusting the control shaft 52 to the desired position, and that this can be done during normal operation of the pump and conveniently from a remote point through a suitable mechanical connection with the arm .68, as will be well understood. i

The pressure of the liquid in the inlet passage of the pump is relatively low and only such as to insure that, for the particular rate of operation required, the rate of flow of the oil or liquid through the passages 14 into the pump chamber I2 is adequate to fill this chamber during the period in the operating cycle that the passages 14 are uncovered by the pumping part I6. A packing ring 16 and a hut 18 are applied to the outer end of the nipple 56 to provide a seal at this point and to hold the part or abutment I4 in a fixed position with respect to the 1 pump casing.

If desired, a pin 88 may be used to further insure against rotation of the nipple 56 and the abutment I4 with respect to the pump casing. L

' When a group of pumps are used, the individual pumps operating respectively to serve the cylinders of a multi-cylinderDiesel engine, for example, it is proposed to connect them in series in the supply line. For this. purpose, the pump is provided with a connection 82 which communicates with the annular passage 64 in the pump casing. A pipe 83 then leads from the connec ion 82 of any particular pump to the connection 62 of the pump next in the series. It will be understood that the pressure in the common supply I line is then maintained sufiiciently high to insure the supply of oil or liquid to all of the pumps at a rate sufficient for the particular rate of opera tion.

If the liquid being pumped is not a sufiicient lubricant itself, it is proposed to provide the pump casing with a lubricating passage .84, as shown in Fig. 4, which will always be in communication with a passage 86 in the pumping part I6. Oil is then supplied byway of a connection 88 to lubricate the adjacent surfaces of the pump casing and the part I6, and the adjacent surfaces of the part I6 and the control element 58.

At the higher rates of operation, it might be required that the rate of flow between the passage 12 and the pump chamber I2 be substantially greater than is possible in theconstruction shown in Figs. 1 to 6. In such cases, it is proposed to modify the construction as shown in Figs. 7 and 8 by providing the control element 58 with a radial passage 98 and the pumping part I6 with a and closed by the pumping part is. It will be seen that this construction is the equivalent of making the passages 14 larger or greater in number, which change might not be possible or practical. The construction and manner of operation in Figs. '7 and 8 are otherwise the same as that in Figs. 1 to 6.

In the modification shown in Fig. 9, the oil or liquid is supplied by way of an inlet connection 94.to a point 96 which is in front of the face 88a of the pumping part I Ba, when the latter is in the position shown, and about to begin the pumping stroke. The control element 58a, corresponding to the control element 58 in Figs. 1 to 6, is provided with the passages 98 and E88 and the annulargroove I82 in its outer face, disposed and communicating as shown.

With the parts in their respective positions as shown in Fig. 9, the passage 98 will be uncovered as soon as the part I6a. starts its stroke in a clockwise direction, whereupon the oil, instead of being pumped out through the valve 42 escapes by way of the passages I82, I88, 98 and a communieating annular passage I84 in the pump casing, back into the supply line.

It will be seen that upon clockwise rotation of the control element 58a to place the passage 98 in a different position, it will be closed by the part I6a during the first part of the pumping stroke, at which time the only outlet for the oil will be through thevalve 42. When the passage 98 is uncovered by the part I60, during the remaining part of the pumping stroke, the oil instead of being forced out through the valve-42 will be pumped back into the feed line through the passages I82, I88, 98, and I84.

It will be noted that in the embodiment of our invention shown in Fig. 9, any pumping of oil through the valve 42 takes place during the first part of the operating stroke, after which the control passages areopened to cause the oil to be pumped back into the supply line. On the other hand, in the embodiments of our invention shown in Figs. 1 to 8, the relief passages are opened during the first part of the pumping stroke, after which these passages are closed and the oil then forced out at the high pressure. through the outlet valve 62. During 'the return or back stroke of the pumping part l6a in Fig. 9, sufficient back pressure might develop on the output side to cause the oil to be pumped through the passages 98 and 8M and thence through the outlet valve 32, rather than out in the opposite direction through passage lfid'into the intake line 94. To prevent this, it is proposed to place a suitable check valve ms in the passage mu as shown in Fig. 14. As shown, this valve closes with the pressure on the intake side so that oilcan only flow through the passages 98 and me toward the pumping chamber and the outlet valve 62.

From the foregoing it will be seen that we have lating of oil in hydraulic brake or shock-absorber systems for automobiles. I

It will be understood that various changes and modifications other than those described can be made without departing from the spirit of our invention or the, scope of the claims,

We claim as our invention:

1. In' a pump of the character described, a cas-,

concentric about its axis, complementary pumping parts disposed in said chamber and each being in the form of a segment of a ring concentric about said axis, one of said parts having a sliding fit in said chamber for rocking movement about said axis relatively with respect to the other part, said pump being provided with an inlet passage for the admission of liquid into said chamber between adjacent ends of said, parts, said pump being provided with an outlet passage forthe expulsion of the liquid from between said ends,

means for controlling the volume of liquid expelled through said outlet passage for each stroke ofsaid rocking part, and means for imparting rocking movement to said one of said parts. v 2. In a pump of the character described, a'casing provided with an annular pump chamber concentric about its axis, complementary pumping parts disposed in said chamber and each being in the form of a segment of'a ring concentric about said axis, one of said parts having a sliding fit in said chamber for rocking movement about said axis relatively with respect to the other part, said pumpbeing provided with an'inlet passage for the admission of liquid into said chamber between adjacent ends of said parts, saidpump being provided with an outlet'passage for the expulsion of the liquid from between said ends, spring means for imparting movement to said rocking part in' one direction, and means for imparting movement to said rocking part in the opposite direction against the action of said spring means,

3. In a pump of the-character described, 8. casfor rocking movement about said axis, said pump being provided with an inlet passage for the admission of liquid into said chamber between adjacent faces of said members, said pump being provided with an outlet passage for the expulsion of the liquid from between said faces, means for controlling the volume of liquid expelled through said outlet passage for each stroke of said pumping member and being in the form of a valve part v having a sliding fit with respect to said members and being rotatable about said axis, means for rotating said control member, and means for imparting rocking movement tov said pumping members 4. Ina pump of the character described, a casing provided with a member disposed and fixed therein, a pumping member disposed in said casing and having a' sliding fit therein for roofing movement about the axis of said casing, said I pumping member being provided with apart complementary to said fixed member and in the form of a segment of a ring, said pump being provided with an inlet passage for the admission of liquid into said casing between adjacent faces of said fixed-member and said part, said pump being provided with an outlet passage for the expulsion of the liquid from between said faces, means for controlling the volume of liquid expelled through said outlet passage for each stroke of said pumping member and being in the form of a valve element disposed in said pumping member and rotatable with respect thereto about said axis, means for rotating said element, and means for imparting rocking movement to said pumping member.

5. In a pump of the character described, a casing, complementary pumping parts disposed within said casing and being in the form of segments of a ring concentric about the same axis, one of said segments having a sliding fit in said casing for rocking movement with respect to the other between said segments, said pump being provided a with an outlet passage for the expulsion of the liquid from between said segments, means for controlling the volume of liquid expelled through said outlet passage for each stroke of the rocking segment and being in the form of a valve eleing, a drive shaft and a control shaft journaled in said casing for rotary movement with respect to each other about the same axis and each extherein and concentric about said axis, said drive shaft being provided at its inner end with a pumping element in the form of asegment of a iing complementary to said abutment and concentric about said axis, said pump being provided with an inletpassage for the admission of liquid into said casing between adjacent faces of said I abutment and said segment, said pump being provided with an outlet passage for the expulsion of the liquid from between said faces, and means "tending outwardly beyond said casing, said casing being provided with an abutment disposed ment about said axis relatively with respect to the I other part, said device being provided with an inlet passage for the admission of liquid into said chamber between adjacent ends of said parts, said device being provided with an outlet passage for the expulsion of the liquid from between said ends, and means for controlling the volume of liquid expelled through said outlet passage for each stroke of said rocking part and being in the form of a valve part having a sliding flt with respect to said complementary parts and being it rotatable about said axis.

JOHN W. BER.

RAYMON L. RQBIOLIO, 

